2. Scientists at Fribourg university in Switzerland have discovered that sticklebacks ejaculate more sperm if first stimulated by a "soft porn" film showing flirting fish.

3. It is thought that the images simulate conditions in the wild where the males rev up their performances if they feel threatened by competitors.

4. It is definitely not connected to a human sexual desire for fish, though if you are over 18, not at work and not going to complain, you can get a flavour of what that may look like here.

5. Such liaisons are rare and seldom documented, though it does recall one Simpsons episode, A Fish Called Selma where Troy McClure (you may remember him from such trivial reports of serious science stories as ... ) is dogged by allegations of the weird things he gets up to at the aquarium.

6. Some, however, believe he is dead. Mob henchman Louie tells his boss, Fat Tony, that he has himself said this. Tony replies: "No, what I said was: 'He sleeps with the fishes'. You see ... "

8. Some of the more functional aspects of fish reproduction have, however, been the greatest mysteries mankind has encountered in the natural world. The circumstances that surround eelspawning are still not fully understood, and it was once thought - by Aristotle, no less - that they spontaneously generated out of mud.

9. With declining fish stocks it would seem churlish to deny them any help they could get. After all, oysters have been helping humans for years.

10. But of course oysters are molluscs, not fish. And let's not go down the dangerous road of shell fetishism. Or into the messy business of prawnography.